Schneider Electric Incandescent Lamp, color, BA 15d socket, 7W, 24V. Created and designed to be used in conjunction with the Harmony XVB, Harmony XVD and Harmony XVP range of products, this incandescent bulb provides a signal instead of a 24V supply voltage. The bulb has a power dissipation of 6.5W and a complementary bulb base: BA15d. This incandescent lighting is also used as an additional accessory for indicator banks and beacons. These types of light bulbs work through an electrical current that passes through a fine filament wire, which heats the filament until it lights up. The heat radiates out of the bulb and a small portion of the energy created is converted into usable light. Keep in mind that this type of lighting produces a large amount of infrared (IR) and ultraviolet (UV) radiation that could damage fabrics and artwork over time.